The present invention relates to a high strength, high conductivity copper alloy wire or cable and a method for manufacturing same, wherein the copper alloy wire consists essentially of from 0.15-1.30% chromium, from 0.01-0.15% zirconium, balance essentially copper.
Copper alloys are the natural choice for conductor wire alloys due to their high electrical conductivity. In fact, commercially pure copper is the most widely used conductor. High performance conductor alloys are required where the properties of copper are not sufficient for a particular application. Thus, in addition to electrical conductivity these alloys must often meet a combination of often conflicting properties. These properties may include strength, ductility, softening resistance and flex life. Indeed, ASTM B624 describes the requirements for a high strength, high conductivity copper alloy wire for electrical applications. These specifications require the alloy to have a minimum tensile strength of 60 ksi, a minimum electrical conductivity of 85% IACS with an elongation of 7-9%. U.S. military specifications for high strength copper alloy cables require a minimum elongation of 6% and a minimum tensile strength of 60 ksi.
Alloying elements may be added to copper to impart strength beyond what can be achieved by cold work. However, if such elements dissolve in the matrix they rapidly reduce the electrical conductivity of the alloy. U.S. Pat. Nos. 4,727,002 and 4,594,116 show high strength, high conductivity copper alloy wire including specific alloying additions.
It is, therefore, desirable to develop a high strength, high conductivity copper alloy wire and a cable therefrom at a reasonable cost and in a commercially viable procedure.
Further objectives of the present invention will appear hereinafter.